Processing of relevant characteristics of complex sounds in normal-hearing listeners and cochlear implant users / Wiebke Heeren.

Format:

Book

Thesis/Dissertation

Author/Creator:

Heeren, Wiebke, 1984- author.

Language:

English

German

Subjects (All):

Auditory perception.

Cochlear implants.

Psychoacoustics.

Physical Description:

1 online resource (v, 214 pages) : illustrations

Edition:

1st ed.

Place of Publication:

Berlin, Germany : Logos Verlag, [2015]

Language Note:

Abstract in English, summary in German.

Summary:

Long description: The auditory processing of complex signals is not yet fully understood making a clearer insight into auditory system processes worth aspiring to. One approach for this purpose is to gain a better understanding of the relations between physical parameters and hearing sensations by means of psychoacoustics. Suitable measures such as loudness help to characterize the perception of sound leading to more sophisticated loudness models which could be useful in optimizing hearing devices such as cochlear implants. The scope of this thesis therefore is the suprathreshold perception of sounds with different spectral, temporal and spatial content in normal-hearing listeners and cochlear implant users. Among others, this covers the applicability of categorical loudness scaling as a fast procedure to assess partial loudness as well as binaural and spatial hearing in cochlear implant users in a free-field measurement setup providing realistic spatial cues.

Contents:

Intro

1 Introduction

1.1 Loudness

1.1.1 Spectral aspects

1.1.2 Temporal aspects

1.1.3 Spectro-temporal aspects

1.2 Spatial hearing

1.2.1 Localization cues

1.2.2 Head related transfer function

1.2.3 Static and dynamic angle discrimination

1.2.4 Binaural masking level difference

1.3 The inner ear and Cochlear Implants

1.3.1 Sound processing in the inner ear

1.3.2 Cochlear Implants

1.4 Motivation and structure of the thesis

2 Spectral loudness summation of nonsimultaneous tone pulses

2.1 Introduction

2.2 Methods

2.2.1 Subjects

2.2.2 Stimuli

2.2.3 Procedure

2.2.4 Statistical analysis

2.3 Results

2.3.1 Experiment 1: Effects of inter-pulse interval

2.3.2 Experiment 2: Effects of pulse duration

2.3.3 Experiment 3: Effect of overall duration

2.3.4 Experiment 4: Effect of reference

2.4 Discussion

2.4.1 Spectral loudness summation for pulse trains

2.4.2 Effect of tone duration in spectral loudness summation

2.4.3 Role of persistence of specific loudness in nonsimultaneous spectral loudness summation

2.4.4 Comparison with data in the literature on nonsimultaneous loudness summation

2.4.5 Residual nonsimultaneous spectral loudness summation

2.4.6 Implications for loudness models

2.5 Conclusions

3 Spectro-Temporal Weighting of Loudness

3.1 Introduction

3.2 Materials and Methods

3.2.1 Ethics statement

3.2.2 Participants

3.2.3 Apparatus

3.2.4 Stimuli and conditions

3.2.5 Procedures

3.2.6 Sessions

3.3 Results

3.3.1 Sensitivity

3.3.2 Spectro-temporal weights

3.4 Discussion

3.4.1 Comparison to previous studies on temporal weights for broadband stimuli

3.4.2 Bandwidth effects in temporal weights

3.4.3 Comparison to previous studies on spectral weights.

3.4.4 Prediction of spectro-temporal weights from temporal and spectral weights

3.4.5 Spectro-temporal weights within loudness models

3.5 Summary and Conclusions

4 Relation between loudness in categorical units and loudness in phons and sones

4.1 Introduction

4.2 Methods

4.3 Results and Discussion

5 Categorical scaling of partial loudness under a condition of masking release

5.1 Introduction

5.2 Methods

5.2.1 Apparatus and Stimuli

5.2.2 Procedure

5.2.3 Subjects

5.3 Results

5.3.1 Categorical loudness scaling

5.3.2 Loudness matching

5.4 Discussion

5.4.1 Comparison of loudness matching and loudness scaling data

5.4.2 Comparison with literature data on masked thresholds

5.4.3 Comparison with literature data at suprathreshold levels

5.4.4 Relation to neural correlates of masking release

5.5 Summary

6 Categorical scaling of partial loudness in CI users

6.1 Introduction

6.2 Methods

6.2.1 Listeners

6.2.2 Apparatus and Stimuli

6.2.3 Procedure

6.3 Results

6.4 Discussion

6.5 Summary

7 Free-field measurement of minimum audible angle and movement angle in cochlear implant users

7.1 Introduction

7.2 Materials and methods

7.2.1 Setup

7.2.2 Stimulus generation

7.2.3 Calibration

7.2.4 Procedure

7.2.5 Listeners

7.3 Results

7.3.1 Minimum audible angle

7.3.2 Minimum audible movement angle

7.4 Discussion

7.4.1 Applicability of setup and signal generation

7.4.2 Minimum audible (movement) angles in CI users

7.5 Summary

8 Summary and Outlook

9 Appendix

9.1 Results of Chap. 5 for the whole level range

9.2 Individual results of the Experiments in Chap. 6

9.3 Individual results of the NH listeners in Chap. 7.

Notes:

"Dissertation zur Erlangung des akademischen Grades doctor rerum naturalium (Dr. rer. nat.), genehmigt durch die Fakultät für Naturwissenschaften der Otto-von-Guericke-Universität Magdeburg."

Ph.D. Otto-von-Guericke-Universität Magdeburg 2015.

Includes bibliographical references (pages VII-XXXII).

Description based on print version record.

ISBN:

3-8325-8779-9

9783832587796